The present invention relates in general to materials handling vehicles, and more particularly, to sensor configurations for detecting objects in or near a path of travel of a vehicle.
Low level order picking trucks are commonly used for picking stock in warehouses and distribution centers. Such order picking trucks typically include load carrying forks, a power unit and a platform upon which an operator may step and ride while controlling the truck. The power unit has a steerable wheel and corresponding traction and steering control mechanisms, e.g., a movable steering arm that is coupled to the steerable wheel. A control handle attached to the steering arm typically includes the operational controls necessary for operating the truck, such as controls for raising and lowering the forks and for controlling the speed and direction (forward or reverse) of the truck.
In a typical stock picking operation, an operator fills orders from available stock items that are located in storage areas provided on both sides of a plurality of aisles of a warehouse or distribution center. The operator drives a low lever order picking truck to a first location where item(s) on a first order are to be picked. In a pick process, the operator retrieves the ordered stock item(s) from their associated storage area(s) and places the picked stock on a pallet, collection cage or other support structure carried by the forks of the order picking truck. The operator then advances the order picking truck to the next location where item(s) are to be picked. The above process is repeated until all stock items on the order(s) have been picked.
The operator normally steps onto the truck platform to ride on the order picking truck when the distance between consecutive picks is longer, for example twenty or more feet (approximately 6.1 meters). Correspondingly, the operator walks alongside the truck when the distance along the route between consecutive picks is short. Accordingly, some order picking trucks include jog switches located on the truck in the vicinity of the forks and/or on or near the control handle. The jog switches can be used by an operator walking alongside the order picking truck to accelerate the truck to a walking speed, typically between approximately 1.6 miles per hour (3.3 kilometers per hour) to around 3.5 miles per hour (5.6 kilometers per hour) to move from one stock pick location to the next stock pick location without the need to step onto the platform of the order picking truck. However, for such actions, the operator is required to interrupt picking while the order picking truck is relocated to the next location. Thus, the operator may be required to move out of a desired working position or modify a desired walking route to reach the jog switches.
It is not uncommon for an operator to be required to repeat the pick process several hundred times per order. Moreover, the operator may be required to pick numerous orders per shift. As such, the operator may be required to spend a considerable amount of time relocating and repositioning the order picking truck, which reduces the time available for the operator to spend picking stock.